Work-gauging means for sewing machines



July 20 1926. 1555925916 E. B. ALLEN WORK cmusme MEANS ,FOR SEWING MACHINES Filed Sept. 20, 1924 2 sheets-sheet 1 1 .1. INVENTOR f flaw .3 WTNES BY M ATTORNEY July 20 1926.

E. B. ALLEN WORK GAUGING MEANS FOR SEWING MACHINES '"Filed Sept. 20 1924 2 Sheets-Sheet 2 INVENTOR {W A. M

WITNES Patented July 20, 1926.

UNITED STATES PATENT ore! EDWARD 1B. ALLEN, OF NEW'TOWN, CONNECTICUT, ASSIGNOR' F110 .ITHEJSINGER .MAN U- FACT'URING COMPANY, 'OF .ELIEABETLH, NEW" JERE EY, A...CQRP.0RATIO;NTOF

JERSEY.

WORK GAUGING iMEAES FOB: SEWING .MAGHINES.

'Applieationjiled.September 20,1924. -Serial No. 733,752.

This invention relates to sewing machines and has for an object to provide workgauging mechanism including laterally movable work-engaging elements which .occupy inoperative or out of the way positions when WOIk is "being introduced to the machine, and aresubsequently moved .to operative positions without special attention on the part of the operator. More ;par 'ticularly, the invention has for an-object to provide worksgauging means for the workclamp: of a buttonhole-sewing .machine to facilitate the rapid Working of accurately centered buttonholes in straps of various .kinds such, for example,"assandal or suspender straps.

According f to. the present. improvement, .the work-Supportsof ethe mac'hine is zPI'OVlded with a pair of reciprocally and laterally movable work centening gauges whiclr are connected :to be operated by. the .usual. nup- -wardly and downwardly .movable workengaging device which. isilowered unto engagement with the work to hold ;the latter for the action of the stitch-forming:inechanism. ilncertain types of sewingmachines, such as straight-away stitching. unacliines, the upper work-engaging device is. ikl'lOWIl as a presserefoot and thework is fed relatively to such foot between consecutive ;penetrations of the sewing needle. Inother types of sewing machines, such .as ,group stitching machines, .the upper work-engaging device is consituted by one or more clam ping feet which:movewith the work .to position the stitches. When the :workis to be removed from or tintroduced'to :the machine, the upper work-engaging :device :is customarily raised, and the gauges,.throughLtheir connection with such device, are aspread :apart and shifted to theirinoperative posi tions. Afterfthe work .isiintroduced to .the machine andzas the upper work-engaging device is being lowered into engagement with the work, .the :gauges are laterally moved to engage and center-the workqbe fore the "work is gripped by :such device. Where the gauging mechanismlisapplied to :a buttonhole sewingpmachine itov-center sthe shanks of strap-ends, it is :desirableitosprovid'e one or :more *strapvend gauges defining a pocket or the ilike'for centering the strapend. 1

To adaptxthe mechanism for centering straps of various widths,jthe connection betweenthe reciprocally movable gauges and the mechanism ,for operating the upper work-engaging. device may be made yielding .in character, sothat such device may continue. its .motion toi ully engage and press upon orclamp the Work after the motion of .the centering ,gaugesis arrested by .the

work.

In .the accompanying .drawingafFig; l .is

.apflan view ofithe work-clamp ofa buttonhole sewing machine embodyingitheinvention. Fig.2 is. asiniilar view with theupper work-clamping feet removed and .showing the work in sewing position. .EFig. '3. is a section on the line 3, 3, Fig. 1, and .Fig. .4 is a perspective view of one of the stationary. gauges.

By way of illustration, the invention .is

disclosed as yembodiedin the workiclamp of t. a group stitching. machine of the lbuttonhole formed on the cross s ide-plate 4:. Secured to the upper. side of the zfiront-end portionrof the cross slide-plate .4 is thetransversely .eX- tending retainer plate 5 the rearwardzedge of which overhangs the zflanges 7 at "the front edges .of the lower worksnpporting plates 8 of the laterally aseparable-ssectlons of the work-clamp. .Disposed .above the work-supporting ,plates .8 are .the upper work-engaging devices or workplamping .feet 9 .carried at the free ends of the usual clamping arms 10, which .are .pivotally mounted at 11 on the fulcrum-blocks 12 carried by :the .plates .8. The upper workengagingmeansor clamping feet are operated by the usual lifting and lowering mech- .anism including the separably connected rock-shaft sections 13 carrying cam-e1ements 14:, a finger-lever'loanda rearwardly extending lever 16 adaptedqtofbe depressed automatically by suitable mechanismwhen the machine is-st-arted osuchmechanism being disclosed, ifor example,:;in the :patent to .Allen, No."15,-82i,1neissued April 1, 31922.

The lower worlesupporting plates 8 and upper worn-engaging;means;;or clam'pnn;

. sitioned relative to such slots if the finished position of the slide-block 32.

buttonhole is to appear where wanted. In working buttonholes in strap-ends, it is essential to sightly work that the buttonholes be located at uniform distances from the extreme ends of the straps, and also that the center lines of the buttonholes coincide with the center lines of the corresponding straps. The strap-end gauging means comprises the gauge-blocks 19 which are secured to the respective arms 20 having their shanks slotted at 21 for passage of fastening screws 22 threaded into the plates 8. The gaugeblocks have their proximate edges 23 in clined to form a V-notch which serves to uniformly position and center the strapends 24. g g

The strap-shanks are centered by means of the reciprocally movable gauge-levers 25, 26 fulcrumed at 27, 28 on the fulcrum block 29 secured to the retainer plate 5. The gauge-levers 25, 26 overhang the work-supporting plates 8 of the removable clampsections and terminate at their free ends in the upwardly bent toes .30 adapted to en gage the side edges of the work-piece.

Mounted in the slideway 31 in the block 29 is the slide-block 32, which is connected to the gauge-levers 25, 26 by means of links 33, 3 f of equal length. The link 34: has an extension constituting a lever-arm 35 by means of which the slide-block is reciprocated and the gauge-levers '25, 26 reciprocally' moved. The linkage is such that the toes 30 of the levers 25, 26 are equi-distant from the center line of the clamp for any Thus, when said levers are closed into engagement with a strapshank they will center it relatively to thewOrk-clamp regardless of its width. The gauge-levers 25, 26 are preferably connected to be operated by the clamp-closing mechanism to insure the centering of the work without special attention on the part of the operator. To this end, one of the rockshaft sections 13 has fixed thereto a depending arm 36 to which is freely pivoted the rearward end of the rod 37, the forward end of which is telescopically received within the rearward end of the tubular rod 38 pivotally connected at 39 to the lever-arm 35. A light spring 40 is disposed within the tubular rod 38 in engagement with the forward end of the rod 37.' When the rockshaft sections 13 are turned to close the work-clamp, the gauge-levers 25, 26 are moved toward one another until the toes 30 engage and center the work. Further approach of the gauge-levers is arrested by the work while the spring 40 yields, so that the turning of the rock-shaft sections 13 fully to clamp-closing position will not force the gauge-levers to distort the work.

A screw 41 passing through the slot 42 in the tubular-rod 38 and threaded into the rod 37 prevents over extension of the rods 38 and 37 and affords a lost-motion positive connection between such rods. The timing is such that the gauge-levers are moved to their work-centering positions before the upper clamping feet 9 grip the work. It will be observed that the gauge-levers 25, 26 do not interfere in any way with the lateral or usual spreading movements of the clamp sections.

A cover-plate 13 having a strap passageway 44 is provided to cover the gauge levers 25, 26 and prevent fouling of the work therewith.

The invention is not to be understood as limited in its application to a buttonhole sewing or other type of group-stitching machine, as it is obviously applicable in its broader aspects to straight-away stitching machines.

Having thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine, the combination with the upper and lower work-clamping elements and clamp-closing mechanism, of reciprocally movable work-centering elements operatively connected to said clampclosing mechanism.

2. In a group-stitching machine, the combination with the work-supporting means, clamping feet and clamp-closing mechanism, of strap-end gauging means disposed adjacent said clamping feet, and reciprocally movable strap-shank gauges connected to be operated by said clamp-closing mechanism.

3. In a group-stitching machine, the combination with the work-supporting means, clamping feet and clamp-closing mechanism, of strap-end gauging means disposed adjacent said clamping feet, reciprocally movable strap-shank gauges, and a yielding ing levers, and means connected to said clamp-closing mechanism for simultaneously moving said levers in opposite directions to gauging position.

6. In a group-stitching machine, the combination with the work-clamp support and removable Work-clamp sections, of w0rkgauging arms pivotally mounted on said support and overlying but free of connection with said sections.

7. A Work-clamp :t'or group-stitching machines having upper and lower work-clamping elements apertured to expose an area of the Work to the action of the stitch-forming mechanism, clamp-closing means, a slideblock movable in a path in line with said apertures, gauge mechanism including gauging-levers fulcrnmed on opposite sides of said path, means including link connections between said slide-block and levers for reciprocally moving the latter, and an operative connection between said clampclosing means and said gauge mechanism for moving said gauge levers to gauging position during the clamp-closing movement of said clamp-closing means.

In testimony whereof, I have signed my name to this specification.

EDWARD B. ALLEN. 

